The present invention relates to exercise methods and apparatus and more particularly, to exercise equipment that facilitates movement of a person""s feet through generally elliptical paths.
Exercise equipment has been designed to facilitate a variety of exercise motions. For example, treadmills allow a person to walk or run in place; stepper machines allow a person to climb in place; bicycle machines allow a person to pedal in place; and other machines allow a person to skate and/or stride in place. Yet another type of exercise equipment has been designed to facilitate relatively more complicated exercise motions and/or to better simulate real life activity. Such equipment typically uses a linkage assembly to convert a relatively simple motion, such as circular, into a relatively more complex motion, such as elliptical. For example, see U.S. Pat. No. 4,185,622 to Swenson; U.S. Pat. No. 5,279,529 to Eschenbach; U.S. Pat. No. 5,383,829 to Miller; U.S. Pat. No. 5,540,637 to Rodgers, Jr.; U.S. Pat. No. 5,882,281 to Stearns et al.; and U.S. Pat. No. 6,080,086 to Maresh et al.
Generally speaking, the present invention provides a novel linkage assembly and corresponding exercise apparatus suitable for linking circular motion to relatively more complex, generally elliptical motion. The present invention may be described in terms of, among other things, an exercise apparatus having two pairs of cranks rotatably mounted on a frame. A left foot supporting assembly is supported by the left cranks, and a right foot supporting assembly is supported by the right cranks. Left and right rocker links are pivotally mounted on the frame and operatively connected to respective foot supporting assemblies. Left and right drawbar links have respective first ends that are operatively connected to respective rocker links, and respective second ends that are constrained to rotate together with the respective cranks. The resulting arrangement links horizontal displacement of the cranks to relatively greater horizontal displacement of a person""s feet.
On one embodiment, the foot supporting assemblies include left and right rails that are rotatably interconnected between respective cranks, and left and right foot skates that are movably mounted on respective rails. The rocker links are operatively connected to respective foot skates and to respective drawbar links. As a result, the rails are constrained to move through respective circular paths relative to the frame, while the foot skates are constrained to move back and forth relative to respective rails.
On another embodiment, the foot supporting assemblies include left and right rollers rotatably mounted on respective cranks, and left and right foot supports supported on respective rollers. The rocker links are operatively connected to respective foot supports and to respective drawbar links. As a result, the foot supports are constrained to move up and down together with respective cranks, and back and forth relative to respective cranks.
On yet another embodiment, which combines features of the previous two embodiments, the foot supporting assemblies include left and right rails that are rotatably connected to respective first cranks, and left and right foot supports that are supported by rollers on respective second cranks. The foot supports are connected in telescoping fashion to respective rails. The rocker links are operatively connected to respective foot supports and to respective drawbar links. As a result, the foot supports are constrained to move up and down together with respective rails, and back and forth relative to respective rails.
Among other things, the present invention may be considered advantageous to the extent that the available stride length is relatively large as compared to overall machine size; the stride length is adjustable through a relatively large range of motion; and/or the foot supports remain in a single, desirable orientation during exercise activity. Various features and/or advantages of the present invention will become apparent from the more detailed description that follows.